1. Technical Field
Embodiments include a venous pressure measurement apparatus, and particularly, to a venous pressure measurement apparatus for non-invasively measuring a mean venous pressure.
2. Description of Related Art
The venous pressure in the vicinity of the right atrium is called a central venous pressure, which indicates a cardiac preload used as an important index to recognize the circulatory dynamics.
The central venous pressure can be invasively measured by inserting a catheter into the vicinity of the right atrium. However, recently, a venous pressure measurement apparatus capable of non-invasively measuring the central venous pressure with a reduced burden to the patient has been developed.
In Unexamined Japanese Patent Publication No. 2010-279654 (“JP 2010-279654”), there is disclosed as related art of the non-invasive venous pressure measurement, in which the artery and the vein are occluded by a cuff applied to the upper arm once, after that, the occlusion of the artery and the vein is sequentially released by gradually reducing the cuff pressure, and, at the same time, these are detected by using a gray scale value of a projection image obtained by irradiating infrared rays onto the leading edge of the antebrachial region, so that the venous pressure is measured based on the cuff pressure when the congestion is released.
However, in “JP 2010-279654”, it does not teach that the venous pressure is measured while a living body is under natural conditions since the vein is congested once, and the venous pressure is measured when the venous blood starts to flow from the congested state. In addition, instruments to irradiate infrared rays and the infrared sensor are necessary.